January in Cairns is the rainiest and the cloudiest month of the year. In January, the weather in Cairns is typically warm. Average daily high temperature in January is about 27 degrees above zero. On average, Cairns has 22 rainy, 4 cloudy, 4 partly cloudy, and 1 sunny day in January. The rains are usually heavy. January as well as February, March, April, and December is considered the most uncomfortable time to visit Cairns.